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The human expiration date: On average, you have 4,680 weeks to live. This means the biggest opportunity cost of all is how you fill the time (in weeks) you have left. It’s a sobering thought, but it can lend to planning for a fulfilling future. Ask yourself: “How can I best spend my X-number of weeks? What should I do more of? Less of? What should I attempt? What should I quit?"

Life’s greatest asset: Time is the one thing you cannot ever get back. While you can cancel a hotel room and get a raise at work, time doesn’t work in the same way. As Raines says, “It's fascinating to me that we try so hard to optimize for every additional dollar, but give no thought to every additional day.” Time wasted can be driven by two main things: apathy (passive routine, remaining on autopilot), as well as hustle (always striving for the most money, determined to win the game, even if you don’t enjoy the work). The opportunity cost of both? Your life.

A new perspective: When you focus on your expiration date, it doesn’t have to be a dark thought, but something that lights a fire for you to live fully. Knowing there will never be a convenient time to make a big move, learning to enjoy the journey (not just the destination) and understanding that the real risk in life is never trying are lessons to be learned in making the most of the weeks you have left.

Mind over matter: It’s easy to get wrapped up in making the perfect investment or financial planning decision, but remember what you’re giving up in the process: The little time we all have left.